The LTE (long-term evolution) wireless communication standard is currently the primary standard for 4G cellular technology. Broadly, LTE supports a wide variety of services, from high bandwidth data services to real-time communication services from a common IP (internet protocol) based network. The LTE standard is based on an OFDM (orthogonal frequency-division multiplexing) method of encoding digital data.
Recently, the United States government has mandated the creation of FirstNet (The First Responder Network Authority) for the purposes of operating and maintaining an interoperable public safety broadband network. It is anticipated that various other governments will adopt similar agencies and public-safety networks. LTE has been selected as the next communication technology to support the public safety networks defined by FirstNet.
It is generally known that OFDM-based systems, such as LTE, are sensitive to timing and frequency synchronization errors. These errors have in the past been exploited for the purposes of jamming attacks which target LTE synchronization symbols to cause denial of service for devices joining an LTE network.
One approach for improving the performance of LTE devices in hostile jamming environments is to make use of adaptive synchronization improvements to the LTE operating environment. Adaptive synchronization is known in the prior art and has been proposed for OFDM based communication systems over power lines (see for example S. Aghajeri and H. Shafiee, “Synchronization in OFDM powerline communication systems in presence of narrowband interferences,” in Proc. International Symposium on Signal Processing and Its Applications, July 2003, vol. 2, pp. 359-362.
However, the prior art has its limitations, particularly in terms of its robustness and performance to different types of interference. For example, there is a need in the art for an improved adaptive synchronization method for applications where there is a threat of partial-band stationary jamming or interference.